Artificial tooth.



J. A. WILLIAMS. ARTIFICIAL TOOTH.

APPLIQATION FILED APR. 18, 1908.

944,836, Patented De0.28,19( )9.

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JOHN A. WILLIAMS, or FORT WAYNE, INDIANA.

ARTIFICIAL TOOTH.

Application filed April 18,1908. Serial No. 427,776.

To all whom it may concern:

Be it known thatI, JOHN A. WILLIAMS, a

citizen of the United States, residing at Fort Wayne, in the county ofAllen, in the State of Indiana, have invented certain new and usefulImprovements in Artificial Teeth; and I do hereby declare that thefollowing is a full, clear, and exact description of the invention,which will enable others skilled in the art to which it appertains tomake and use the same, reference being had to the accompanying drawings,which form'part of this specification.

My invention relates to improvements in artificial teeth.

The prime object of my present invention is to provide a comparativelycheap, substantial, and reliable artificial tooth formed of a porcelainfront and a metallic backing so united as to admit of immediate,convenient and economical repairs where either or any portion of thetooth is broken or damage My invention consists of an artificial toothformed of two interlocking portions or sections, one section being ametal base or backing provided upon its inner face with a transverseslot or recess whose sides are substantially parallel and the lower ofwhich sides is slightly undercut, and the upper end of which may have aforwardly projecting shoulder adapted to embrace the corresponding endof the front section; the othersection being a porcelain facing providedupon its inner face with a transverse ledge or flange slightlydovetailed on its lower edge adapted to form an interlocking engagementand dovetailed union with the said transverse recess.

The principal novel feature of my invention resides in the constructionand codperative relation'of the coacting interlocking sections, andparticularly in the form of dovetailed union of the tooth sections.

I In the accompanying drawings similar reference numerals indicate likeparts in the several views in which- Figure 1 is a side elevation of myinvention showing the manner of uniting the intel-locking parts. Fig. 2is a detail perspective of the porcelain facing section looking towardits inner face showing the dovetailed transverse ledge. Fig. 3 is alongitudinal central section of Fig. 1, and Fig. 4 id a perspectivedetail of the metal backing or body portion of the toothshowing theunder-' cut transverse recess on its inner face.

The metallic section 1, preferably of gold, and of proper dimensions,may have its upper end provided with a forwardly projecting shoulder 2of any desired contour, adapted to overhang and substantially embracethe upper end of the facing thereof, though this shoulder is notessential to my invention and may be emitted at pleasure withoutaffecting the character and efficiency of the same. This metallicsection constitutes both the body of the tooth and the backing thereof,and is provided, substantially midway of its ends, with a dovetailtransverse groove or recess 3 of proper dimensions adapted to receivethe interlocking portion of the facing. The undercut is upon the lowerside of the recess to interlock with the flange 5 for the purposehereafter described. This metallic section 1 has its Specification ofLetters Patent. Patented Dec, 28 1909 longitudinally rounded or convexedto conform to the contour of the outer face of the natural tooth, asshown in Figs. 1 and 3.

The upper end of the facing section 3 is, of course, beveled to snuglyfit the lower face of the shoulder 2, as shown when such shoulder isemployed, and is providd u on its'inner face approximately midway 0 itsends with a transverse slightl dovetailed ledge or flange 5 adapted toorm a snug interlocking union with the said recess 3 of the metalsection. It is essential that the undercut or dovetailed portion of theflange 5 should-be upon the lower edge thereof to resist the lateralstrains upon the porcelain facing in use-which tend to disunite it fromits backing. As no such strains are felt by the up er end of the facingthe upper edge of the ange 5 is not dovetailed; and for the y furtherreason that otherwise the facing can not be placed in position from thefront, as is necessary in repairing a damaged or broken facing which hasanother artificial tooth upon each side thereof and firmly united to itsmetal backing in the usual manner.

The component parts or sections of my improved artificial tooth thusdescribed are firmly secured together by means of suitable cement. Themanner of mounting dentures of this character in position of use is wellunderstood, and the manner of uniting the component parts is obvioussince it is apparcut that they can be united by first inserting theledge 5 in the recess 3 and then the balance of the ledge all from thefront, and can readily be permanently thus united by means of a propercement. In case either the porcelain facing 4 or the metal backing 1 1sbroken or otherwise damaged the dentist can readily disunite them andsave the undamaged section, and then conveniently substitute a newcompanion section as before.

It is obvious that when the parts are thus united and secured by cementthey cannot be displaced or separated by any ordinary usage. It is alsoevident that my construc-- tion of the dovetailed connection of theparts of the tooth is specially adapted to resist the biting strainsthereon, and at the same time rmits the convenient replacing of a newacing upon an old backin from the front without detaching the backlngfrom'its supporting denture.

Having thus described my invention and the manner of employing the same,what I desire to secure by Letters Patent is:

In an artifical tooth the combination of two interlocking sections, onesection being a porcelain front with a beveled front edge and atransverse integral ledge undercut at its lower edge only, and the othersection being a metal backing with a projecting upper edge and atransverse recess under cut at its lower edge only.

Signed by me at Fort Wayne, Allen county, State of Indiana, this 16thday of April, 1908.

- JOHN A. WILLIAMS. Witnesses:

WATTS P. DENNY,

AUGUSTA Vienna.

